1. Field of the Invention
The present invention relates to a semiconductor device and a method of manufacturing the same. More particularly, the invention relates to a trench isolation type semiconductor device having reduced junction leakage current in an element isolation region, and a related method of manufacture.
This application claims priority from Korean Patent Application No. 10-2006-0004115 filed on Jan. 13, 2006, the subject matter of which is hereby incorporated by reference in its entirety.
2. Description of the Related Art
A semiconductor device commonly includes a plurality of active and passive elements formed on a semiconductor substrate. Different types of semiconductor devices perform different functions depending on how the various elements are arranged and electrically connected. Accordingly, most of the elements forming a particular semiconductor device must be electrically isolated from one or more adjacent (or proximate) elements in order to properly function. Various structures have been conventionally adopted to provide electrical isolation. One such structure is the so-called Shallow Trench Isolation (STI) structure. The STI structure has excellent element isolation characteristics while only occupying a relatively small surface area of the substrate. These qualities make the STI structure very advantageous in attempts to manufacture semiconductor devices having increased integration.
The STI structure is often formed by first forming a trench region of defined geometry in the substrate and then filling the trench with an insulating material, such as silicon oxide. The insulating material may be formed in the trench using such common fabrication processes as Chemical Vapor Deposition (CVD).
However, the use and formation of the STI structure in not without its problems. The inclusion of STI structures in a semiconductor device may increase the overall manufacturing complexity, and the loss (or lifting) of the insulating material filling the trench may occur, such as during a subsequently applied oxide film cleaning, or wet/dry etching process. When the insulating material in the STI structure is imperfectly formed or damaged/removed during subsequent fabrication processes, junction leakage current may be generated at a boundary surface (e.g., edge portions) between a proximate electrically active region of the substrate and the element isolation region formed by the STI structure. The presence of such leakage current causes deterioration in the performance characteristics of the semiconductor device.